-LRB- CNN -RRB- -- Gabrielle Giffords submitted her resignation as a U.S. representative from Arizona before Congress on Wednesday , and an initial reaction might be a sense of despair about her decision to step aside . Many have imposed a narrative of national recovery on Giffords ' ability to run for her office again and take her oath in a clear strong voice .

But in this case , it would be a mistake to confuse holding public office with redemption . A congressional seat is not supposed to be a plot point for Hollywood endings , and by passing up the chance to run again , Giffords has demonstrated a respect for the principles of representative democracy .

The authors of the Constitution intended Congress to be a rotating body , free from the cults of personality and lifetime sinecures that characterized European governance . Although it is human nature to see a kind of triumph in being able to come back to one 's job after an injury , Giffords understands that the office belonged not to her but to southern Arizona . She made the decision after a year of rehabilitation , and she deserved that time to make a hard call with the best evidence .

Her choice this week recalls an old observation of Harry Truman , who said he always tried to remember that the crowds cheering and the bands playing `` Hail to the Chief '' were not for him personally . They were for the office of the presidency .

The office of Congress may also be too small for Giffords . This is a body that commands the respect of 8 % of the electorate : a record low . And despite the illusion of glamour that surrounds it , the actual work can be physically taxing and spiritually dreary . Traveling back and forth from Washington each week , visiting the House floor multiple times a day for procedural votes , sweet-talking big donors , finding positions that will please the district without making you feel like a sellout -- all of these can take their toll .

After her bruising re-election fight of 2010 -- one of the nastiest races in recent local memory , with an eerie pallor of violence hanging over it -- Giffords herself doubted whether she wanted the job much longer .

She now has a golden opportunity to start a `` Gabrielle Giffords Institute '' for the study of gun violence or mental health care reform or solar energy or whatever public policy issue she wants to emphasize . Her moral authority and influence may be better used outside the halls of Congress , where she would have been inevitably fettered by the daily grind of politics and partisanship .

In her video announcement , she said : `` I will return , and we will work together for Arizona and this great country . '' And we should take her at her word , even if that does n't mean a return to elective office .

To be sure , this is not the future anyone would have wanted . There is enormous cruelty in her injury -- the robbery of her ability to speak -- which was one of her truly exceptional qualities .

I remember thinking near the end of her first campaign for Congress , in 2006 , that the only thing that could deny her a victory over her maladroit opponent would be some kind of epic goof made during a campaign rally or a debate -- a vague exclamation taken out of context or a damaging statement made in passion . But such a possibility was remote . `` Gabrielle does n't really make mistakes , '' I told a friend . She possessed a preternaturally strong sense of control over her words .

This was also true in private conversation . Giffords had that quality , cherished among leaders , to gauge the emotional temperature of the person she was with and adjust her own bearing accordingly . There were many times in our friendship when she managed to say the unexpectedly perfect thing in the moment : a key piece of advice , a joke , an anecdote that had precise relevance .

There is a picture of her that is difficult for me to view . It is the last photograph of her taken before the 16 seconds of gunfire that would change everything . She is standing in front of the Safeway on January 8 , 2011 , looking intently at a middle-aged woman named Doris Tucker , who had been next in line to speak with her

In back of her is the plate-glass front of the grocery store on which the smeary reflections of a few people are visible . Out of this crowd a gunman was about to emerge . But what dominates the frame is Giffords ' expression , one of wordless concentration and interest in what Tucker was saying . It was a look that I knew well .

The loss of her ability to find the words in conversation easily is an awful blow . But the Giffords I know wo n't surrender the primary motivating force in her life , which is the urge to make a difference in the public sphere and to use her talents to make life better for those around her . That was what motivated her first run for Congress five years ago . She is leaving national elective office in the same way she came in : with class and dignity .

It would be a mistake to think of this as a defeat because it is not the neat Hollywood ending we had hoped for . This is not Hollywood . And this is not an ending .

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The opinions expressed in this commentary are solely those of Tom Zoellner .

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Tom Zoellner : We have put a narrative of national recovery on Giffords ' ability to run again

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By stepping down , Giffords shows a respect for principles of democracy , he says

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Her moral authority and influence may be better used outside Congress , Zoellner says

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Zoellner : Her driving motivation is to make a positive difference in public life , and she will